Improvement in lamp-chimneys



E. JONES.

Lamp Chimney. No. 100.637. 5 1 h Patented March 8, 1870.

i Idwam? JJzzes 1k 11$ eat/0 may UNITED STATES PATENT OFFICE EDWARDJONES, OF SOUTH BOSTON, MASSACHUSETTS.

IMPROVEMENT IN LAMP-CHIMNEYS.

Specification forming part of Letters Patent No. 100,637, dated March 8,1870.

hereby declare thesame to be fully described in the followingspecification, and-represen ted in the accompanying drawings, of which-Figure 1 is a side elevation, and Fig. 2 a vertical section, of achimney containing my improvement.

In order to produce the maximum amount of light, the point whichrequires the greatest attention is the due adjustment of the'supply ofair. If too much be given the gas burns with a blue feebly-luminousflame. The effect of too great a supply of air is to completely consumethe gas without allowing time for the separation of carbon, and it burnswith a blue t'eebly-luminous flame, with a loss of illuminating power.

On the other hand, the supply of air must not be too limited, otherwisethe light hecomes red from the reduction of temperature, the carbonpasses of unburned, the oxygen being insufficient to complete thecombustion, and the flame becomes smoky. The effect also of a too rapiddraft isto contract the 'cone of luminous particles; but with a properdraft a large flame is produced, and more light is obtained. 1 haveaccomplished this adjustment of the supply of air by contract ing theupper part of the chimney to about one-half the diameter of the bottomor lower part, substantially asshown and described.

In the drawings, A denotes a chimney which is cylindrical until withinabout an inch of its top, it being there reduced to the frustum of acone, as shown at a, whereby the .mouth'b of discharge of the chimney isreduced to a diameter about one-half of the opening 0 at the lower endof the chimney.

l have found by accurate experiments with a photometer, that with achimney so made the light of the flame of the burner is increased aboutone hundred per cent. over what it would be with a glass chimney madeWholly cylindrical. V

The taper and proportions of the chimney may vary somewhat from thoseshown in the drawings without materially varying the effect of thecontraction of the upper end of the chimney.

I claim as my invention An Argand-burner chimney, contracted at itsupper part in manner and so as to reduce its mouth of discharge,substantially as described.

E. JONES.

Witnesses:

R. H. EDDY, F. P. HALE, Jr.

